Various alarms have been developed, some of which include movement sensitive devices, but none show a device switch to turn off the alert light and to turn on an alarm.
Altman et al, U.S. Pat. No. 4,520,351, issued May 28, 1985 shows a manual deadman switch which sets an alarm, the alarm being delayed for a pre-set period of time after the manual deadman switch is operated. The deadman switch can be deactivated only by coded switches. Although Altman shows a light for indicating when the battery is working, and the coded switch being in a closed position, the light is also operated by the deadman switch. To operate the Altman device, both the manual deadman switch and the coded switch need to be manipulated before the alert light comes on. For the proper operation of the Altman, the deadman switch must be held down by the operator. This is inconvenient for the operator, and results in a more complex system than is shown in the present invention, in which an alert state is also includes a delay before the alarm goes on, after release of the deadman switch, to prevent spurious alarms, this increases the complexity of the Altman device.
In addition, the Altman device includes a complex coded switch which needs to be manipulated both the set the alarm in the alert state, and to turn the alarm off if the alarm is activated. Such a switch is difficult to manipulate.
Demuth, Canadian Patent 867,512, issued Mar. 30, 1971, shows a position sensitive alarm, which sets off an alarm when a persons body is in other than normal position. It also includes a radio transmitter and receiver, and a display, for indicating the location of the person. No light is shown.
Yannuzzi, Canadian Patent 958,098, issued Nov. 19, 1974, shows a medical alert device which includes a position sensitive switch and an audible alarm, together with a manual override. No light is shown, and no related manual switch is shown.
Clendening, Canadian Patent 1,213,335, issued Oct. 28, 1986, shows an alarm which is attached to a belt having a lock. Once the alarm is set off, it cannot be turned off until the belt is removed.
Schwartz, Canadian Patent 1,238,386, issued June 21, 1988, shows a position sensitive switch of a particular type, having mercury in a frusco- conical well and does not show an alert light.
Ashley et al, U.S. Pat. No. 3,579,221, issued May 18, 1971, shows a deadman switch, together with an alarm, in conjunction with a radio detection and location device.
Barkley, U.S. Pat. No. 3,634,885, issued Jan. 11, 1972, shows a medical alert device, in which a position sensing switch (a mercury filled attitude switch) operates an audible message alarm, containing medical information on a patient. There is also shown an override switch and a backup switch.
Hubert, et al, U.S. Pat. No. 4,110,741, issued Aug. 29, 1978 shows a movement monitor. If movement ceases, for a pre-set period of time, an alarm is activated.
Polley, U.S. Pat. No. 4,262,285, issued Apr. 14, 1981, shows a spring biased rod normally held closed by a cap or person's hand. When released, it activates an alarm with a pin mechanism such that the alarm cannot be deactivated.
Berg, U.S. Pat. No. 4,404,549, issued Sept. 13, 1983, shows a manual switch to set off an alarm, which requires a key switch to turn off the alarm.
Bussing, U.S. Pat. No. 4,692,749, issued Sept. 8, 1987, and Takagaki, U.S. Pat. No. 4,158,197, issued June 12, 1979, show a personal distress alarm in which in individual must activate a switch or part of the alarm device to initiate an alarm.
None of the prior art patents show all of the features in the present invention, and none shows a device with a single switch to set the alert light, and a single impact switch to set off the alert light and turn on an alarm.